Pontiac 1998 Trans Sport Owner's Manual page 274

Then here are some tips:
Make sure your vehicle
is
well ventilated, with a
comfortably cool interior.
0
Keep your eyes moving. Scan the road ahead and
to the sides. Check your mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest, service
or parking area and take a nap, get some exercis'e, or
both. For safety, treat drowsiness on the highway as
an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in flat or rolling terrain.
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